diff options
| author | Jia-Ju Bai <baijiaju1990@gmail.com> | 2020-11-19 04:52:18 +0300 |
|---|---|---|
| committer | Kalle Valo <kvalo@codeaurora.org> | 2020-11-24 18:06:38 +0300 |
| commit | 8b2c13b2e5dab8f2ace44cc775096c6fae0a6f72 (patch) | |
| tree | 52604964538367edff27d6b4fa059e8a6e89b9cf | |
| parent | ff76548338947c2c45b7aaf1d182e331398279b7 (diff) | |
| download | linux-8b2c13b2e5dab8f2ace44cc775096c6fae0a6f72.tar.xz | |
rtlwifi: rtl8723ae: avoid accessing the data mapped to streaming DMA
In rtl8723e_tx_fill_cmddesc(), skb->data is mapped to streaming DMA on
line 531:
dma_addr_t mapping = dma_map_single(..., skb->data, ...);
On line 534, skb->data is assigned to hdr after cast:
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data);
Then hdr->frame_control is accessed on line 535:
__le16 fc = hdr->frame_control;
This DMA access may cause data inconsistency between CPU and hardwre.
To fix this bug, hdr->frame_control is accessed before the DMA mapping.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201119015218.12220-1-baijiaju1990@gmail.com
| -rw-r--r-- | drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c b/drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c index e3ee91b7ea8d..340b3d68a54e 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c @@ -528,12 +528,12 @@ void rtl8723e_tx_fill_cmddesc(struct ieee80211_hw *hw, u8 fw_queue = QSLT_BEACON; __le32 *pdesc = (__le32 *)pdesc8; - dma_addr_t mapping = dma_map_single(&rtlpci->pdev->dev, skb->data, - skb->len, DMA_TO_DEVICE); - struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data); __le16 fc = hdr->frame_control; + dma_addr_t mapping = dma_map_single(&rtlpci->pdev->dev, skb->data, + skb->len, DMA_TO_DEVICE); + if (dma_mapping_error(&rtlpci->pdev->dev, mapping)) { rtl_dbg(rtlpriv, COMP_SEND, DBG_TRACE, "DMA mapping error\n"); |